node.js - 如何使用 Node js保存base64图像？

Question

我正在使用 nodejs 保存 base64 图像，它将我的图像保存在确切的路径，但显示错误。

请帮我找出错误。

这是我的代码

var express = require('express');
var router = express.Router();

const fs = require('fs');
const mime = require('mime');


const path = './uploads';

router.post('/register', (req, res, next) => {
  const base64Image = req.body.image;

  const matches = base64Image.match(/^data:([A-Za-z-+\/]+);base64,(.+)$/);
  response = {};
  if (matches.length !== 3) {
    return new Error('Invalid input String');
  }

  response.type = matches[1];
  response.data = new Buffer(matches[2]);
  let decodedImg = response;
  let imageBuffer = decodedImg.data;
  let type = decodedImg.type;
  let extension = mime.extension(type);
  let fileName = 'image.' + extension;

  try {
    fs.writeFileSync(path + '/' + fileName, imageBuffer, 'utf8');
    return res.send({ status: 'success' });
  } catch (e) {
    next(e);
  }

  return;

});

module.exports = router;

感谢任何解决方案!

Answer 1

你犯的错误是当你创建一个缓冲区时你没有指定编码。你应该像这样创建缓冲区:

new Buffer() is deprecated use Buffer.from() instead.

let buff = Buffer.from(m[2],'base64');//编码类型base64

基本代码片段

const fs =  require('fs')
let a =  'base64ImageString'
let m =  a.match(/^data:([A-Za-z-+\/]+);base64,(.+)$/);
  
let b =  Buffer.from(m[2],'base64');
fs.writeFile('image.png',b,function(err){
  if(!err){
    console.log("file is created")
  }
});

此外，当您将缓冲区写入文件时，您不必传递编码类型，但如果写入字符串，则必须传递。

查看此演示 https://repl.it/repls/GrimOfficialLocations

But it is not advised to send an image as base64 string. It is inefficient for large images. base64 roughly takes 33% more bits than its binary equivalent. I recommend you to check this out: Upload base64 image with Ajax